Method of lining a conduit using a scrim-reinforced pipe liner

ABSTRACT

A method for repairing a conduit using a tube-shaped liner comprising a single layer of resin-absorbent fabric having a polymeric coating attached to an outer wall of the tube and a reinforcing layer connected to an inner surface of the tube. The liner is impregnated with a resinous material capable of curing and hardening and inverted under pressure into the conduit to be repaired such that the reinforcing layer is pressed against the interior of the conduit. The resinous material is allowed to cure and harden, creating a lining to the conduit. The single layer of fabric may be a non-woven material, such as a felt. The conduit to be lined may be a sewer pipe, and the reinforcing material may be a woven scrim. The woven scrim may be capable of preventing longitudinal stretch of the liner tube while allowing radial stretch.

FIELD OF THE INVENTION

The present invention relates to a method and device for repairing aconduit using a scrim-reinforced pipe liner. More particularly, but notexclusively, it relates to a method and device for lining a pipe using aliner comprising a single layer of resin-absorbent fabric having a scrimlayer associated with a first surface of the absorbent fabric and acoating associated with the opposite surface of the single layer ofresin-absorbent fabric.

BACKGROUND OF THE INVENTION

Pipes and conduits have been restored for many years using a variety ofrehabilitation and pipelining techniques. One such technique is referredto as “cured-in-place pipelining” or “CIPP.” This technique includestaking a resin-absorbent sheet, impregnating the sheet with resin,placing the resin-impregnated sheet against the wall of a pipe, andallowing the resin to cure and harden. The resin-absorbent sheets aregenerally known as “liners.”

Some liners used for cured-in-place pipelining applications use a layerof resin-absorbent fabric in association with a coating, reinforcing,and/or shielding layer. For example, U.S. Pat. No. 4,009,063 to Wood isone of the first patents issued for such liners. The '063 patentdiscloses a two-layered liner comprising a laminate of non-woven feltand plastics sheet material. The '063 patent also suggests the use of asecond sheet of material in the form of a woven scrim web to reinforcethe liner. The patent fails to disclose where the scrim web isincorporated into the liner. Furthermore, the '063 patent discloses alaminate for use with a so-called “pull-in-and-inflate” method that doesnot utilize an inversion process for installation. Inventor Eric Woodwas also issued U.S. Pat. No. 4,836,715, which discloses a similar linerwhere a woven layer may be used as a reinforcing layer within sectionsof a felt layer. As such, this patent does not specifically disclose theplacement of a scrim layer on the surface of the liner.

Another example of such liners are disclosed in U.S. Pat. No. 5,501,248and U.S. Patent Application Number 2010/0243091, where the use of apolymeric coating reinforced with a scrim associated with aresin-absorbent fabric layer is described. Since the polymeric coatingand scrim are attached or otherwise abut, these liners are subject todelamination of the polymeric coating from the liner after placementwithin a host pipe.

U.S. Pat. No. 5,535,786 to Mäkelä, et al discloses a pipe liner ofvarious constructions where one or more felt layers are used inconjunction with a knitted reinforcement layer and an optional coating.Even though the several embodiments of this patent disclose a variety ofconfigurations of the felt layer, reinforcement layer, and coatinglayer, there is no embodiment where the reinforcement layer is connectedto one surface of a single layer of felt with a coating on the oppositesurface.

U.S. Pat. No. 5,868,169 to Catallo discloses the use of a layer ofreinforcing fibers and a layer of resin-absorbing material fixedlyattached and positioned adjacent to the layer of reinforcing fibers sothat the layers of resin-absorbing material, when saturated with resin,shield the layer of reinforcing fibers from water or other corrosivematerials that contact the liner. The patent teaches that withconventional cured-in-place liners using fiberglass, the fiberglassfibers located on the inner and outer surfaces of the liner are exposedto the water and other corrosive materials. Due to capillary or wickingaction, the water and other corrosive materials are absorbed into thetiny spaces adjacent to the exposed fiberglass fibers. The absorption ofwater and other corrosive materials enhances the expansion andcontraction of the resin and fiberglass, thereby further deterioratingthe bond between the resin and fiberglass. Corrosive reactions with theresin/fiberglass laminant also exacerbate the deterioration of the bondbetween the resin and fiberglass. Because of the wicking action, thespace between the resin and fiberglass fibers becomes progressivelylarger and larger. In addition, as the space between the resin and agiven fiber grows in size and length, previously unexposed fiberglassfibers adjacent to the exposed fibers become exposed to the water andother corrosive materials. Over time, the wicking of water and othercorrosive materials into the laminant will destroy the bond between theresin and the fiberglass fibers. When this occurs, the reinforcingeffects of the fiberglass is lost causing the liner to lose much of itsstructural strength, thereby ending the useful life of the linerprematurely. As with the Wood patents, the Catallo patent fails to teachthe inversion of such a liner into a pipe during installation.

U.S. Pat. No. 6,732,763 to Williamson, et al. addresses many of the sameproblems as the '169 patent, but claims to additionally prevent stretch.U.S. Pat. No. 6,732,763 discloses a stretch-resistant liner for a pipehaving a support sleeve positioned between two sealing sleeves. As thesupport layer is sandwiched between two sealing layers, the flexuralstrength of the cured liner is not enhanced because the reinforcement isplaced close to the neutral plane of the liner.

Yet another liner used in cured-in-place pipelining having a layer ofresin-absorbent fabric in association with a coating, reinforcing,and/or shielding layer is disclosed in U.S. Pat. No. 6,708,729 to Smith.This patent discloses a multi-layered liner construction where a scrimweb is attached to a layer of resin-absorbent material to act as areinforcing layer. An inner reinforcing layer comprising bundles ofreinforcing fibers may be attached to the scrim web, folded over, andstitched along the edge to form a tube. A resin-absorbent layer orlayers are wrapped about the inner reinforcing tubular layer and joinedat the edges to form a tube. An outer reinforcing layer of reinforcingfiber bundles held together by longitudinal stitching is then wrappedaround the resin-absorbent layer to form an outer tubular layer with theends of the bundles of reinforcing fibers overlapping. The result ismulti-layered liner with a scrim web near one surface of the liner andan impermeable coating near the opposite surface of the liner.

As such, problems remain in the art and a need exists for an improvedmethod and means for repairing a pipe using a scrim-reinforced pipeliner.

BRIEF SUMMARY OF THE INVENTION

It is therefore a principal object, aspect, feature and/or advantage ofthe present invention to provide a device and method for providing alining to a conduit, such as a sewer pipe, which improves over or solvesthe problems and deficiencies in the art.

Other objects, features, aspects, and/or advantages of the presentinvention relate to a device and method for lining a conduit where aliner coating is unlikely to delaminate from the cured product.

Further objects, features, aspects, and/or advantages of the presentinvention relate to a method of lining a conduit with a liner where theliner is flexible enough for inversion prior to placement within a pipe,yet is capable of providing enhanced flexural strength after the linerhas cured.

Further objects, features, aspects, and/or advantages of the presentinvention relate to a new apparatus and method for lining a conduitwhere a scrim layer is used to reinforce a liner tube where the scrimallows for some radial stretching of the tube but prevents longitudinalstretch.

One aspect of the invention includes a method for providing a lining toa conduit where a single sheet of resin-absorbent fabric having a firstsurface and a second surface is provided. A reinforcing material isconnected to the first surface of the single sheet of resin-absorbentfabric, and a polymeric coating is imparted to the second surface of thesingle sheet of resin-absorbent fabric. The single sheet ofresin-absorbent fabric is formed into a tube such that the secondsurface is the outer surface of the tube. The tube is then inverted intothe conduit under pressure so that the reinforcing material is pressedagainst the inner wall of the conduit. The method may includeimpregnating the sheet of fabric with a material capable of curing andhardening and allowing the material to cure and harden. The fabric maybe a non-woven material, such as a felt. The conduit to be lined may bea sewer pipe, and the reinforcing material may be a woven scrim. Thewoven scrim may be capable of preventing longitudinal stretch of theliner tube while allowing radial stretch.

These and other objects, features, aspects, and/or advantages of thepresent invention will become apparent with reference to theaccompanying specification and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a material used to produce a lineraccording to one embodiment of the present invention where a reinforcinglayer is connected to a surface of the liner opposite a coating layer.

FIG. 2A is a perspective view of a woven scrim material.

FIG. 2B is a perspective view of a reinforcing layer of the presentinvention including locking members.

FIG. 3 is a perspective view of the material used to produce a liner inFIG. 1, showing where the material is placed into a liner tube prior toinversion within a conduit to be lined.

FIG. 4 is a perspective view of the liner tube of FIG. 3, showing wherethe liner tube has been inverted within a conduit to be lined and wheresections of the liner have been cut away to show the relationship of thecomponents of the liner within the conduit.

FIG. 5 is a sectional view of the liner of the present invention withina conduit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

This invention relates to a method and device for repairing a conduitusing a reinforced pipe liner. More particularly, but not exclusively,it relates to a method and device for lining a sewer pipe using a linercomprising a single layer of absorbent material having a scrim layerassociated with a first surface of the absorbent material and a coatingattached to the opposite surface of the absorbent material.

The following definitions of terms are employed throughout thespecification and claims:

“Attached” is defined as having a mechanical attachment by fastening orjoining.

“Connected” is defined as associated with or considered as related. Asused herein, the term “connected to” does not require physicalattachment, rather simply an association or relationship.

“Fabric” is defined as any cloth made from yarn or fibers by methodssuch as weaving, knitting, felting, etc. It contemplated that the fabricbe made of a material of any construction as long as the material iscapable of absorbing a resin.

The terms “invert,” “inversion,” and “inversion process” are all meantto describe a method where a pipe liner is turned inside out, where whatwas the interior of the liner becomes the exterior. These terms arecommonly used synonymously with the terms “evert” or “eversion.”

“Layer” is defined as a portion of material covering or forming a part.

“Reinforcing material” is defined as a material that provides additionalstrength to a lining material before, after, or during curing of aresin.

“Scrim” is defined as a loosely woven fabric.

Referring now to the drawings wherein like numerals refer to like parts,FIG. 1 is a sectional view of a material used to produce a lineraccording to one embodiment of the present invention. The liner 20 isshown as a reinforced liner for lining the interior of a conduit, suchas a sewer pipe. The liner 20 includes three layers: a coating layer 10,a single layer of a resin-absorbent fabric 12, and a reinforcing layer14. The coating layer 10 is attached to a first surface of the singlelayer of the resin-absorbent fabric 12 and the reinforcing layer 14 isconnected to a second surface of the resin-absorbent fabric 12 oppositethe first surface.

The single layer of resin-absorbent fabric 12 is preferably constructedof a non-woven material, such as felt. A non-woven material is generallya material having a porous sheet structure made from interlocking layersor networks of fibers, filaments, or filamentary structures. The fibers,filaments or filamentary structures may be directionally or randomlyoriented and are bonded by friction, cohesion, or adhesion. While ispreferred that the resin-absorbent fabric 12 be a non-woven material,the present invention contemplates that the single layer ofresin-absorbent fabric 12 may also be a woven material. Woven materialsare typically composed of yarns or threads running lengthwise in thematerial and filling threads interlaced with lengthwise threads atapproximately right angles. It is also contemplated that theresin-absorbent fabric be a composite or combination of a plurality offabrics (such as wovens and non-wovens) joined together to act as asingle layer. It should be appreciated that the resin-absorbent fabricmay be any other fabric capable of absorbing a resinous material capableof curing and hardening, including but not limited to layers of felt,linen, cotton, synthetic fibers, natural fibers, polymers, and blends.

Felt material is preferred because felt lends itself to great tolerancesand variances in the manufacturing process. Felt may be easily needledor stretched, and it is commercially available in an array of differentconstructions. For instance, felt can be produced as a composite offibers having various deniers. Adjusting the denier of the felt allowsfor certain fibers of a felt sheet to become substantially integratedwith a polymeric coating. As such, molten polymers easily coat felt, asthe fibers are readily incorporated into the polymer coating. This isespecially true if the fibers of the felt are constructed of a materialcompatible with the polymer coating. Additionally, felt is easilyproduced in sheets of various densities and thicknesses. In applicationswhere the polymer is a molten state during the application process, thepolymeric coating may melt or otherwise incorporate a portion of thefelt fibers into the coating. Therefore, a felt sheet having asubstantial thickness and density should be used for the liner of thisinvention. The thickness should be chosen such that the liner has thecapability of absorbing enough resinous material to create a liningwithin a conduit in conformance with applicable ASTM standards, such asASTM-F1216.

The first surface of the layer of resin-absorbent fabric 12 includes apolymeric coating 10, comprising an impervious polymeric coating orfilm, preferably a thermoplastic polyurethane (“TPU”). The coating 10may be made of other polymeric materials, such as polyethylene (PE) orpolyvinyl chloride (PVC). However, the polymeric coating 10 may be anyother polymer that may be coated onto a resin-absorbent fabric. Forexample, some polymers considered for use with this invention includepolyurethanes, polyethylenes, polyvinylchlorides, butyls, rubbers,cellophane nitrates, neoprenes, polyester, or combinations thereof. ATPU is preferred because TPU is an example of a polymeric material thatmay be left inside the conduit after the lining process is complete,acting as a coating to the interior of the conduit. Additionally, acertain grade of TPU may be chosen to coat a specific type of conduit.TPU is commercially available in two different grades: ester grade andether grade. An ether grade material is best suited for applicationswhere the conduit transports water and other aqueous effluents, as ethergrade thermoplastic material does not degrade in aqueous conditions.Ester grade material is best suited for applications where the conduittransports natural gas, oil, or other organic effluents, as ester gradethermoplastic material does not degrade in the presence of organicmaterials or solvents. Additionally, TPU is compatible for adhesion tomany resinous materials capable of curing and hardening. For instance,it has been found that a TPU coating easily adheres to most epoxy resinsafter curing and hardening of the epoxy. As such, it is envisioned thatmany other resinous materials capable of curing and hardening may beutilized with an array of polymeric coating materials that provideenhanced bonding capabilities of the coating to the liner. As such, theresinous material capable of curing and hardening may be a thermosetresin, and ambient cure resin, an ultraviolet curing resin, a polyester,a vinyl ester, an epoxy, or any other resin capable of curing andhardening.

The polymeric coating 10 is attached to the single layer ofresin-absorbent fabric 12. The polymeric coating 10 may be attached byany known method of attaching a polymeric film to a fabric, includingbut not limited to adhesion, extrusion, dip/immersion coating, kisscoating, knife coating, spraying, or bar coating. It is noted that amethod may be utilized that maximizes the strength of the bond of thepolymeric coating 10 to the single layer of resin-absorbent fabric 12for applications where the coating 10 remains inside the pipe to act asa coating to the cured liner 20.

The polymeric coating 10 on the liner 20 may be used to ensure aleak-free tube and provide a slick surface to the lining after theconduit is lined. As such, the polymeric coating must have a thicknesssuch that the liner is impermeable, yet remains flexible enough tonegotiate bends in the pipeline and allow the lining tube to be invertedinto the pipeline under fluid pressure. If the polymeric coating 10 istoo thick, the liner 20 will be unable to undergo an inversion processinto the conduit to be repaired. The polymeric coating 10 should have athickness of about 2-50 mils, preferably 4-10 mils. It should be notedthat the thickness of the polymeric coating 10 should not be so thin asto become weak, as the coating provides a smooth surface for effluentsto travel through the conduit with little resistance due to friction,thus increasing the flow rate observed within the lined conduit.

The second surface of the layer of resin-absorbent fabric 12 includes awoven or knitted reinforcing layer 14 connected or attached thereto. Thereinforcing layer 14 may be described as a woven or knitted sheet,capable of providing reinforcement to the liner 20 once connected to thesingle resin-absorbent material 12. In some embodiments, the reinforcinglayer 14 may be a knitted material. The knitted material may be capableof allowing stretch in one direction of the material, but not allowingstretch in the other direction of the fabric, as shown for example inU.S. Pat. Nos. 5,732,573 and 6,804,978. In several embodiments, a scrimis used as the reinforcing layer. A scrim 30 may be described as a wovensheet generally including a warp 32 and a weft 34, as shown in FIGS. 2Aand 2B. The intersection of the warp 32 and the weft 34 may be 90degrees or it may be less or more than 90 degrees. The intersection ofthe fibers that comprise the scrim may be configured in any way, as longas the scrim provides some reinforcement to the fabric in twodirections, such as the x- and y-axis of a flat sheet. Preferably, thereinforcing layer 14 will provide reinforcement or stretch-resistancealong a first direction of the sheet, and less reinforcement orstretch-resistance in the opposite direction of the sheet.

In some embodiments, it may be advantageous to utilize a reinforcinglayer 14 capable of absorbing an adhesive or the like. In such anembodiment, the reinforcing layer 14 may be attached to the single layerof resin-absorbent material 12 by an adhesive carried on the reinforcinglayer 14. In other embodiments, it may be advantageous to includelocking members 36 associated with the scrim 30 that encourage amechanical lock between the liner and the scrim before and/or aftercuring of the resin, as shown in FIG. 2B. Locking members 36 may begenerally described as projections, indentations, or irregularitiesconnected or attached to the reinforcing layer 14 or scrim 30 that embedwithin the single layer of resin-absorbent fabric and/or the materialcapable of curing and hardening. Locking members 36 are illustrated asrings, but locking members having a variety of shapes such as hooks orloops may be used to create a mechanical bond between the scrim and thesingle layer of resin-absorbent material before installation. Afterinstallation, the locking members 36 may be used to create a mechanicalbond between the scrim and the material capable of curing and hardening.

When the liner 20 is placed into the form of a tube, as shown in FIG. 3,the reinforcing layer 14, depicted as a woven scrim, should providereinforcement in the longitudinal and radial directions of the tube. Thereinforcing layer 14 should be on the interior of the tube. The scrimmay be constructed of strands, yarns, strings, or the like. The scrimmay be attached to the resin-absorbent material by needling, stitching,adhering using an adhesive, or the like. A needling process ispreferably used to connect the scrim to the resin-absorbent fabric bypunching small needles through the fabric, lifting small, random fibersof the resin-absorbent material above the scrim, and locking the scrimto the surface of the resin-absorbent material. Utilizing a needlingprocess to connect the scrim to the single layer of resin-absorbentfabric 12 may result in an embodiment where the reinforcing layer 14 isattached to the resin-absorbent fabric 12 for the entire length of thefabric. Alternatively, the scrim may be attached near the ends of thetube, allowing the scrim to move freely across the body of the liner 20prior to installation.

In yet even further embodiments, the reinforcing layer 14 or scrim maycomprise two different materials in order to allow varying degrees ofpre-cure stretch or post-cure strength in different directions of theliner 20. The first material may comprise an elastic yarn or thread thatallows stretch in a first direction of the fabric, where the firstmaterial may enhance the mechanical properties of the cured liner tosome degree. The second material may comprise a non-stretching materialthat limits stretch in a second direction of the fabric, and may enhancethe mechanical properties of the cured liner. The mechanical propertiesthat may be enhanced include tensile strength, tensile modulus, flexuralstrength, or flexural modulus. It is envisioned that many differentmaterials used for the reinforcing layer 14 may enhance the mechanicalproperties of the cured liner.

It is preferred that the liner be flexible enough to be inverted into aconduit under pressure. It is preferred that when the liner isinstalled, the polymeric coating is the new conduit interior, and thescrim is adjacent to the walls of the conduit. It is noted that in someinstances, the scrim may not physically touch the conduit wall, as resinwill fill the area between the scrim material and the conduit wall. FIG.4 illustrates a perspective view where the liner 20 of FIG. 3 has beeninverted within a conduit 40 to be lined, and sections of the conduit 40and sections of the liner 20 have been cut away to show the relationshipof the components of the liner 20 within the conduit 40. It is easilyseen that the reinforcing layer 14, depicted as a scrim, is placedagainst the inner wall of the conduit 40 to be lined. The single layerof resin-absorbent fabric 12 is also expanded against the wall of theconduit 40 after a resinous material capable of curing and hardening isapplied to the fabric. This arrangement is also depicted in thesectional view provided in FIG. 5.

The inversion process may be performed using any method known in theart. For instance, a control rope or line may be attached to a closedfirst end of the liner. The control rope or line acts to provide acontrolled inversion and to alert an installation technician when theliner is fully inverted within the conduit. The opposite second end ofthe liner may be attached to a unit that applies pressure to theexterior of the liner, so that the lining assembly may invert into theconduit to be lined. Such a unit is generally called an “inversionvessel” or a “shooter.” The second end of the liner may be attached to ahose of the inversion vessel after pulling the closed first end of theliner into the inversion vessel by the rope or line. The opposite secondend may be attached to the hose by banding, taping, cam locks, or thelike. The inversion vessel also includes a fluid line that suppliesfluid pressure to the inversion vessel. The fluid may be hydraulicfluid, water, air, and/or other fluids. However, the fluid is preferablyair. The hose is aligned with an access bore of the conduit to be lined,pressure is supplied to the inversion vessel via the fluid line, and thelining assembly is inverted into the conduit to be lined. Additionally,the methods of the present invention may be utilized to line lateralsewer pipes or the junction of a main and lateral sewer pipe, utilizingmethods such as those described in U.S. Pat. Nos. 6,039,079 and6,994,118, which are hereby incorporated by reference in theirentireties.

There are several advantages of using the methods associated with aliner of the construction described above. First, flexural strength isenhanced in the cured liner. Since the reinforcing materials or scrim isoutside of the neutral plane, the material that comprises the scrim willincrease the ability of the cured liner to resist deformation under loadduring the flexural test. This is because the reinforcing fibers orscrim are the “extreme fibers,” or the inner and outer edges of thecured liner sample. When the cured liner material is bent, only theextreme fibers are at the largest stress. Therefore, if those fibers arefree from defects, the flexural strength will be controlled by thestrength of those intact fibers (the strength of the material comprisingthe scrim). However, if the scrim lies in the neutral plane of theliner, then all of the fibers in the material are at the same stress,and failure will initiate when the weakest fiber reaches its limitingtensile stress. Many of the known prior art liners utilize aconstruction where the scrim (if present) lies within the neutral planeof the liner.

Another advantage of placing the scrim on the side of theresin-absorbent material opposite the polymeric coating is the fact thatplacing the coating and the scrim on the same side may lead todelamination of the coating from the cured liner. Since the scrim willgenerally limit the stretch of the material in different directions, thescrim acts as the only limiting force because the polymeric coating andresin-absorbent material are generally flexible or capable ofstretching. Therefore, while the liner is inflated and/or placed againstthe walls of the conduit, the resin-absorbent material and the polymericcoating stretch while the scrim does not. Since many of the prior artdisclosures include some structure where the coating and scrim areattached, this invention avoids the delamination problem by completelydissociating the polymeric coating from the scrim.

The liner as disclosed may be used to provide a lining to the interiorof a conduit to be repaired or sealed, preferably a low-pressure pipe,such as a sewer pipe. However, it is envisioned that the liner of thepresent invention may be used to seal or repair many other types ofconduits, including but not limited to other low-pressure conduits, suchas an HVAC duct; a pressurized pipe, such as a potable water pipe or gasline; or a conduit for the transport of other materials, such aselectrical conduit.

In operation, the methods and liners of the present invention includethe following: a single sheet of resin-absorbent fabric having a firstsurface and a second surface is provided. A reinforcing material orlayer is connected to the first surface of the single sheet ofresin-absorbent fabric, and a polymeric coating is imparted to thesecond surface of the single sheet of resin-absorbent fabric. The singlesheet of resin-absorbent fabric is formed into a tube such that thesecond surface is the outer surface of the tube. The single sheet offabric is impregnated with a resinous material capable of curing andhardening. The tube is inverted into the conduit under pressure so thatthe reinforcing layer or material is pressed against an inner wall ofthe conduit. The resinous material capable of curing and hardening isallowed to cure and harden, providing a new interior lining to theconduit to be repaired.

The result of practicing the embodiments and methods of this inventionis a lining to a conduit where a coating is attached to the liningwithin the conduit. The coating provides a smooth interior surface foreffluents to travel through the conduit with little resistance due tofriction. Additionally, the liner used to form the conduit lining is notconstricted during installation, therefore very few bulges or buncheswill appear in the cured conduit lining. Additionally, the coating willnot separate or fall into the conduit, as practicing the methods of thisinvention allows the coating to remain within the lined conduit whenoptimal materials are chosen for the coating and resin-absorbent fabric.

The invention has been shown and described above with the preferredembodiments, and it is understood that many modifications,substitutions, and additions may be made which are within the intendedspirit and scope of the invention. From the foregoing, it can be seenthat the present invention accomplishes at least all of its statedobjectives.

1. A method of lining a conduit, comprising: providing a single sheet ofresin-absorbent fabric having a first surface and at opposite secondsurface; connecting a reinforcing material to the first surface of thesingle sheet of resin-absorbent fabric; imparting a polymeric coating tothe second Surface of the single sheet of resin-absorbent fabric;forming the single sheet of resin-absorbent fabric into a tube such thatthe second surface is an outer surface of the tube; inverting the tubeinto the conduit such that the reinforcing material is pressed againstan inner wall of the conduit.
 2. The method of claim 1, wherein thesingle sheet of resin-absorbent fabric comprises a single layer of felt.3. The method of claim 2, wherein the reinforcing material is attachedto the single layer of felt by a needling process.
 4. The method ofclaim 1, wherein the reinforcing material is attached to the tube near afirst end and a second end of the tube.
 5. The method of claim 1,wherein the reinforcing material is attached to the single layer ofresin-absorbent fabric with an adhesive.
 6. The method of claim 1,wherein the reinforcing material is a woven scrim.
 7. The method ofclaim 6, wherein the scrim allows radial stretch of the tube andprevents longitudinal stretch of the tube.
 8. The method of claim 1,wherein the reinforcing material is knitted.
 9. The method of claim 1,further comprising: impregnating the single sheet of resin-absorbentfabric with a material capable of curing and hardening; and allowing thematerial capable of curing and hardening to cure and harden.
 10. Amethod for providing a lining to an interior of a conduit, comprising:providing a tube comprising a single layer of resin-absorbent fabrichaving a polymeric coating attached to an outer wall of the tube and areinforcing layer connected to an inner surface of the tube;impregnating the single layer of resin-absorbent fabric with a resinousmaterial capable of curing and hardening; inverting the tube under fluidpressure into the conduit such that the reinforcing layer is pressedagainst the interior of the conduit; and allowing the resinous materialto cure and harden.
 11. The method of claim 10, wherein the conduit is asewer pipe.
 12. The method of claim 11, wherein the single sheet ofresin-absorbent fabric comprises a single layer of felt.
 13. The methodof claim 11, wherein the reinforcing layer is attached to the singlelayer of felt by a needling process.
 14. The method of claim 11, whereinthe reinforcing layer is a wove scrim.
 15. The method of claim 14,wherein the scrim allows radial stretch of the tube and preventslongitudinal stretch of the tube.
 16. A liner for providing a lining toan interior of a conduit, comprising: a resin-absorbent material havinga first surface and an opposite second surface; a reinforcing materialattached to the first surface of the resin-absorbent material; and animpermeable coating attached to the second surface of theresin-absorbent material.
 17. The liner of claim 16, wherein theresin-absorbent material comprises felt.
 18. The liner of claim 16,wherein the impermeable coating comprises a polymer.
 19. The liner ofclaim 16, wherein the reinforcing material comprises a woven scrim. 20.The liner of claim 16, wherein the reinforcing material is attached tothe first surface of the resin-absorbent material by needling, and theimpermeable coating is attached to the second surface of theresin-absorbent material by an adhesive.